edit_file

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

With no annotations, the description carries the full burden of behavioral disclosure. It accurately states the core mutation (replacing text), but omits important behavioral details such as what happens when the target text is not found, whether changes are reversible, and any permission requirements. The replaceAll semantics are left to the schema.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is a single, well-structured sentence with no filler or redundant content. It front-loads the key verb 'Update' and the resource 'existing file'.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a simple edit tool, the description plus schema are mostly sufficient. However, with no annotations and no output schema, the description lacks information about failure behavior (e.g., target not found) and return values, which an agent would need to fully understand the tool's behavior.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 100%, with clear descriptions for path, target, replaceAll, and replacement. The tool description only restates 'target text' and 'new text', adding no additional semantic detail beyond what the schema already provides, so the baseline of 3 is appropriate.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states a specific action ('Update an existing file') with a specific method ('replacing target text with new text'), distinguishing it from sibling tools like write_file or create_directory. The verb and resource are unambiguous.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

The phrase 'existing file' clearly indicates this tool is for modifying existing files, not creating or reading. This provides clear context for when to use it, though it does not explicitly name alternative tools or exclusion scenarios.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.